The present invention relates to a force application apparatus which may be longitudinally extended in any desired configuration to apply the force along lines defining such configuration. The present apparatus is particularly suitable for the operating of strip steel knives, for the application of pressure along a line or curve in a plane or in space.
U.S. Pat. No. 3,815,464 discloses a single stroke cutter operated by an expandable hose for severing a seat belt in an emergency. A repeated cutting operation is not possible with this type of structure. The single stroke apparatus is also not suitable for applying the force along a three-dimensional curve.
U.S. Pat. No. 2,363,779 is representative of the prior art in which expandable hose sections are arranged to cover a large surface area corresponding in size, for example, to the surface area of a wall panel which is to be glued together from several panel components.
U.S. Pat. No. 3,822,627 discloses a press which is operated by an inflatable cushion in the form of a membrane. The pressure is applied to the entire surface area and not only along the lines defined, for example, by the configuration of a strip steel knife.
In the prior art it is not possible to assemble the force application apparatus from modular components into modular units which may be arranged and rearranged for applying a force precisely along a line rather than to an entire surface area, whereby the line may be curved in a three-dimensional space.